818609 has 4 divisors (see below), whose sum is σ = 893040. Its totient is φ = 744180.

The previous prime is 818603. The next prime is 818621. The reversal of 818609 is 906818.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 818609 - 2⁸ = 818353 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 818609.

It is not an unprimeable number, because it can be changed into a prime (818603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37199 + ... + 37220.

It is an arithmetic number, because the mean of its divisors is an integer number (223260).

2⁸¹⁸⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

818609 is a deficient number, since it is larger than the sum of its proper divisors (74431).

818609 is a wasteful number, since it uses less digits than its factorization.

818609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74430.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 818609 is about 904.7701365540. The cubic root of 818609 is about 93.5460609793.

Subtracting 818609 from its reverse (906818), we obtain a square (88209 = 297²).

The spelling of 818609 in words is "eight hundred eighteen thousand, six hundred nine".